by David L. Kirp

Does preschool work? Although early education has been widely praised as the magic bullet that can transport poor kids into the education mainstream, a major new study raises serious doubts.

Since 2004, Tennessee has offered state-subsidized prekindergarten, enrolling more than 18,000 of the state’s neediest 4-year-olds. An early evaluation showed that, as you’d expect, youngsters who attended pre-K made substantial gains in math, language and reading. But, startlingly, the gains had evaporated by the end of kindergarten.

Those first results were alarming, and worse was yet to come.

A just-released study tracks the same kids to third grade. There’s still no evidence that the children benefited cognitively from preschool. They may be better socialized to school life — a skill, emphasized in preschool, that may well bring long-term benefits — but many of them haven’t mastered the three Rs. That’s terrible news, since being a proficient reader by third grade is widely regarded as the best predictor of high school graduation.

Pre-K critics will again pounce on the results. “Devastating for advocates of the expansion of state pre-K programs,” wrote Russ Whitehurst, a senior fellow at the Brookings Institution, commenting on the first-round evaluation. It’s an “I told you so” moment for Tennessee State Representative Bill Dunn, who slammed his state’s prekindergarten as “like paying $1,000 for a McDonald’s hamburger.”

When a nationwide evaluation of Head Start, the federal government’s preschool program, reported similarly disappointing outcomes three years ago, Mr. Whitehurst delivered a blistering critique. “The best available evidence raises serious doubts that a large public investment in the expansion of pre-K for 4-year-olds will have the long-term effects that advocates tout.” Pre-K was generally thought to be better than Head Start, but that doesn’t seem to be the case in Tennessee.

Have the claims made for early education been overblown? Not necessarily. Consider what’s happening in Boston. A randomized study showed that prekindergartners there gained between four and seven months’ progress in reading and math, and those gains persisted: 27 percent more of Boston’s preschool children scored “proficient” or better on the state’s rigorous third-grade exams.

What’s the difference between Boston and Tennessee? In a word, quality. “Tennessee doesn’t have a coherent vision,” Dale Farran, a Vanderbilt professor and the Tennessee study’s co-author, told me. “Left to their own devices, each teacher is inventing pre-K on her own.”

Boston’s teachers are taught to understand the complexities of child development, and receive abundant coaching from knowledgeable veterans. The curriculum is calculated to get children’s minds in gear. “Too often, children sit in a circle and the adult does all the talking,” says Jason Sachs, who runs Boston’s public preschools. “Here, children take much more of an active role. They learn about the concept of length by comparing the shadows they cast when lying on the ground. They learn about measurement by producing a guide to making light blue. They collaborate in figuring out how to make their city a better place — an assignment merging reading, math, art and science — and get to present their work at City Hall.”

Boston isn’t the only pre-K success story. In New Jersey, poor children who went to prekindergarten and are now in fifth grade have closed 20 to 30 percent of the achievement gap between poor students and the nationwide average. Lasting achievement gains have also been recorded in North Carolina, Michigan and Tulsa, Okla. A long-term study of youngsters who attended Chicago’s Child-Parent Centers showed that they had a 29 percent higher high school graduation rate and a 42 percent lower arrest rate for a violent offense than their peers. Economists calculate that every dollar invested in those centers generated $7.10 in benefits.

Recent evidence from Head Start is also positive. That program has been revamped — almost every teacher has a B.A., the curriculum is more hands-on, and more coaching is being provided. Centers with weak results are shuttered. Consequently, test scores are improving. “The newest standards incorporate the latest research to make the program more effective,” says Linda Smith, who runs Head Start.

Money doesn’t guarantee good outcomes, but it helps. It pays for well-educated, experienced teachers, small classes and one-on-one coaching. “There are no easy routes to preschool success,” says W. Steven Barnett, a Rutgers economist and the director of the National Institute for Early Education Research. “It takes time, money and a relentless focus on quality — but it has been done.”

Even as more 4-year-olds attend pre-K, many states are delivering it on the cheap. While Boston spends $10,000 for each preschooler, in 2014 the average expenditure, nationwide, was $4,125. That’s $1,000 less (adjusted for inflation) than the 2002 average — and a third of what’s spent for each K-12 student. In education, as in much of life, you get what you pay for.

__________

David L. Kirp, a contributing writer, is a professor of public policy at the University of California, Berkeley, and a senior fellow at the Learning Policy Institute.